libMesh
cell_hex8.h
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1 // The libMesh Finite Element Library.
2 // Copyright (C) 2002-2025 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
3 
4 // This library is free software; you can redistribute it and/or
5 // modify it under the terms of the GNU Lesser General Public
6 // License as published by the Free Software Foundation; either
7 // version 2.1 of the License, or (at your option) any later version.
8 
9 // This library is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 // Lesser General Public License for more details.
13 
14 // You should have received a copy of the GNU Lesser General Public
15 // License along with this library; if not, write to the Free Software
16 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 
18 
19 
20 #ifndef LIBMESH_CELL_HEX8_H
21 #define LIBMESH_CELL_HEX8_H
22 
23 // Local includes
24 #include "libmesh/cell_hex.h"
25 
26 namespace libMesh
27 {
28 
55 class Hex8 final : public Hex
56 {
57 public:
58 
62  explicit
63  Hex8 (Elem * p=nullptr) :
65  {}
66 
67  Hex8 (Hex8 &&) = delete;
68  Hex8 (const Hex8 &) = delete;
69  Hex8 & operator= (const Hex8 &) = delete;
70  Hex8 & operator= (Hex8 &&) = delete;
71  virtual ~Hex8() = default;
72 
76  virtual ElemType type () const override { return HEX8; }
77 
81  virtual unsigned int n_nodes() const override { return num_nodes; }
82 
86  virtual unsigned int n_sub_elem() const override { return 1; }
87 
91  virtual bool is_vertex(const unsigned int i) const override;
92 
96  virtual bool is_edge(const unsigned int i) const override;
97 
101  virtual bool is_face(const unsigned int i) const override;
102 
107  virtual bool is_node_on_side(const unsigned int n,
108  const unsigned int s) const override;
109 
110  virtual std::vector<unsigned int> nodes_on_side(const unsigned int s) const override;
111 
112  virtual std::vector<unsigned int> nodes_on_edge(const unsigned int e) const override;
113 
118  virtual bool is_node_on_edge(const unsigned int n,
119  const unsigned int e) const override;
120 
125  virtual bool has_affine_map () const override;
126 
130  virtual Order default_order() const override;
131 
136  virtual std::unique_ptr<Elem> build_side_ptr (const unsigned int i) override;
137 
141  virtual void build_side_ptr (std::unique_ptr<Elem> & elem,
142  const unsigned int i) override;
143 
144  // Avoid hiding deprecated version with different signature
145  using Elem::build_side_ptr;
146 
151  virtual std::unique_ptr<Elem> build_edge_ptr (const unsigned int i) override;
152 
156  virtual void build_edge_ptr (std::unique_ptr<Elem> & edge, const unsigned int i) override;
157 
158  virtual void connectivity(const unsigned int sc,
159  const IOPackage iop,
160  std::vector<dof_id_type> & conn) const override;
161 
165  static const int num_nodes = 8;
166  static const int nodes_per_side = 4;
167  static const int nodes_per_edge = 2;
168 
173  static const unsigned int side_nodes_map[num_sides][nodes_per_side];
174 
179  static const unsigned int edge_nodes_map[num_edges][nodes_per_edge];
180 
190  const Point & x0, const Point & x1, const Point & x2, const Point & x3,
191  const Point & x4, const Point & x5, const Point & x6, const Point & x7);
192 
198  virtual Point true_centroid () const override;
199 
204  virtual Real volume () const override;
205 
209  virtual BoundingBox loose_bounding_box () const override;
210 
211  virtual void permute(unsigned int perm_num) override final;
212 
213  virtual void flip(BoundaryInfo *) override final;
214 
215  ElemType side_type (const unsigned int s) const override final;
216 
217 protected:
218 
223 
224 
225 
226 #ifdef LIBMESH_ENABLE_AMR
227 
231  virtual Real embedding_matrix (const unsigned int i,
232  const unsigned int j,
233  const unsigned int k) const override
234  { return _embedding_matrix[i][j][k]; }
235 
241 
243 
244 #endif // LIBMESH_ENABLE_AMR
245 };
246 
247 } // namespace libMesh
248 
249 #endif // LIBMESH_CELL_HEX8_H
static const int num_nodes
Geometric constants for Hex8.
Definition: cell_hex8.h:165
virtual std::vector< unsigned int > nodes_on_side(const unsigned int s) const override
Definition: cell_hex8.C:97
virtual std::unique_ptr< Elem > build_edge_ptr(const unsigned int i) override
Builds a EDGE2 built coincident with edge i.
Definition: cell_hex8.C:161
ElemType
Defines an enum for geometric element types.
virtual std::unique_ptr< Elem > build_side_ptr(const unsigned int i) override
Builds a QUAD4 built coincident with face i.
Definition: cell_hex8.C:146
Order
defines an enum for polynomial orders.
Definition: enum_order.h:40
A Node is like a Point, but with more information.
Definition: node.h:52
Node * _nodelinks_data[num_nodes]
Data for links to nodes.
Definition: cell_hex8.h:222
Hex8 & operator=(const Hex8 &)=delete
virtual void connectivity(const unsigned int sc, const IOPackage iop, std::vector< dof_id_type > &conn) const override
Definition: cell_hex8.C:175
The Hex8 is an element in 3D composed of 8 nodes.
Definition: cell_hex8.h:55
virtual std::unique_ptr< Elem > build_side_ptr(const unsigned int i)=0
The Hex is an element in 3D with 6 sides.
Definition: cell_hex.h:36
IOPackage
libMesh interfaces with several different software packages for the purposes of creating, reading, and writing mesh files.
This is the base class from which all geometric element types are derived.
Definition: elem.h:94
virtual Real volume() const override
A specialization for computing the area of a hexahedron with flat sides.
Definition: cell_hex8.C:415
virtual std::vector< unsigned int > nodes_on_edge(const unsigned int e) const override
Definition: cell_hex8.C:104
The libMesh namespace provides an interface to certain functionality in the library.
virtual unsigned int n_sub_elem() const override
Definition: cell_hex8.h:86
static const unsigned int side_nodes_map[num_sides][nodes_per_side]
This maps the node of the side to element node numbers.
Definition: cell_hex8.h:173
static const Real _embedding_matrix[num_children][num_nodes][num_nodes]
Matrix that computes new nodal locations/solution values from current nodes/solution.
Definition: cell_hex8.h:240
ElemType side_type(const unsigned int s) const override final
Definition: cell_hex8.C:526
virtual Order default_order() const override
Definition: cell_hex8.C:139
static const int num_edges
Definition: cell_hex.h:74
static const int num_children
Definition: cell_hex.h:75
static const unsigned int edge_nodes_map[num_edges][nodes_per_edge]
This maps the node of the edge to element node numbers.
Definition: cell_hex8.h:179
The BoundaryInfo class contains information relevant to boundary conditions including storing faces...
Definition: boundary_info.h:57
static const int nodes_per_edge
Definition: cell_hex8.h:167
Hex8(Elem *p=nullptr)
Constructor.
Definition: cell_hex8.h:63
virtual void permute(unsigned int perm_num) override final
Permutes the element (by swapping node and neighbor pointers) according to the specified index...
Definition: cell_hex8.C:457
virtual ElemType type() const override
Definition: cell_hex8.h:76
virtual bool is_node_on_side(const unsigned int n, const unsigned int s) const override
Definition: cell_hex8.C:87
virtual bool has_affine_map() const override
Definition: cell_hex8.C:121
virtual bool is_face(const unsigned int i) const override
Definition: cell_hex8.C:82
virtual Point true_centroid() const override
We compute the centroid of the Hex using a customized numerical quadrature approach that avoids unnec...
Definition: cell_hex8.C:407
static const int nodes_per_side
Definition: cell_hex8.h:166
Defines a Cartesian bounding box by the two corner extremum.
Definition: bounding_box.h:40
virtual ~Hex8()=default
virtual void flip(BoundaryInfo *) override final
Flips the element (by swapping node and neighbor pointers) to have a mapping Jacobian of opposite sig...
Definition: cell_hex8.C:508
virtual Real embedding_matrix(const unsigned int i, const unsigned int j, const unsigned int k) const override
Matrix used to create the elements children.
Definition: cell_hex8.h:231
virtual bool is_edge(const unsigned int i) const override
Definition: cell_hex8.C:77
DIE A HORRIBLE DEATH HERE typedef LIBMESH_DEFAULT_SCALAR_TYPE Real
virtual bool is_node_on_edge(const unsigned int n, const unsigned int e) const override
Definition: cell_hex8.C:110
virtual BoundingBox loose_bounding_box() const override
Builds a bounding box out of the nodal positions.
Definition: cell_hex8.C:450
static const int num_sides
Geometric constants for all Hexes.
Definition: cell_hex.h:73
static Point centroid_from_points(const Point &x0, const Point &x1, const Point &x2, const Point &x3, const Point &x4, const Point &x5, const Point &x6, const Point &x7)
Class static helper function that computes the centroid of a hexahedral region from a set of input po...
Definition: cell_hex8.C:336
virtual unsigned int n_nodes() const override
Definition: cell_hex8.h:81
virtual bool is_vertex(const unsigned int i) const override
Definition: cell_hex8.C:71
LIBMESH_ENABLE_TOPOLOGY_CACHES
Definition: cell_hex8.h:242
A Point defines a location in LIBMESH_DIM dimensional Real space.
Definition: point.h:39